1. Field of the Invention
This invention relates to an improved button applicator having a one-rotation clutch which is linked to a foot pedal for caulking upper and lower button elements through a fabric piece, more particularly to a button applicator of this kind with a safety apparatus.
2. Description of the Prior Art
In case of a button applicator with a one-rotation clutch, a foot pedal is applied to release a clutch and bring down a punch for caulking button elements for the purpose of holding and straining a fabric piece by hands of an operator. However, it is attended with danger in case that fingers of the operator happen to stay between a punch and a die.
A button applicator which can be operated in safety is disclosed in Japanese Laid Open Utility Model Publication No. 56-143218. This button applicator has a manual safety lever. According to this prior art, even if a foot pedal is stepped, a stopper maintains to engage with a claw of a clutch and a punch is not brought down as long as the manual safety lever is not operated. More detailed explanation of this prior art is as follows; First, the manual safety lever is operated to engage an actuating lever to the stopper. When the foot pedal is stepped, the stopper is pivoted by the actuating lever and releases the claw of the clutch. And finally, the clutch rotates to bring down the punch for caulking upper and lower button elements through a fabric piece.
According to this prior art, unless the manual safety lever is not operated, fail-safe is assured. However, after the manual safety lever is operated, the punch is brought down as soon as the foot pedal is stepped to release the clutch. Although the safety can not be secured, the fabric piece must be held to be strained by hands of an opertor for exact positioning of the button elements. Therefore, in case that fingers of the operator happen to stay between the punch and a die, this work carries a lot of danger for the operator.